Blast furnace



Sept. 29, 1959 H. w. HOCHBERGER BLAST FURNACE 2 Sheets-Sheet 1 FiledOct. 30, 1957 R m m w HENRY m HOCHBERGER P 1959 H. w. HOCHBERGER2,906,520

BLAST FURNACE 2 Sheets-Sheet 2 I Filed Oct. 30, 1957 l/VVE/VTOR HENRY WHOCHBERGER Attorney BLAST FURNACE Henry W. Hochberger, Chicago, 111.,assignor to United States Steel Corporation, a corporation of New JerseyApplication October 30, 1957, Serial No. 693,466

2 Claims. (Cl. 26631) This invention relates to a blast furnace and moreparticularly to the utilization of the flue dust in a blast furnace. Theblast furnace gas passes through a dust catcher where the flue dust isseparated out and periodically recovered. After recovery it is generallysintered and charged into the furnace as part of its burden. It has beensuggested in the patent to Dougherty No. 1,024,623 that the flue dust bereturned to the furnace without sintering but the apparatus and methodof doing this is such that it is diflicult to retain the flue dust inthe furnace.

It is therefore an object of my invention to provide apparatus forautomatically charging flue dust into the furnace without sintering insuch a manner that a large portion of the flue dust will remain in thefurnace.

This and other objects will be more apparent after referring to thefollowing specification and attached drawings, in which:

Figure l is .an elevation, with parts broken away and shown in section,of the apparatus of my invention;

Figure 2 is a view taken on the line IIlI of Figure 1; and

Figure 3 is a View taken on the line III--III of Figure 1.

Referring more particularly to the drawings, the reference numeral 2indicates the top of a blast furnace having the usual big bell hopper 4and big bell 6 mounted at the top thereon. The big bell 6 has a bell rod8 fastened to the top thereof by which the big bell is raised intocontact with the lower part of the big bell hopper or lowered to permitdischarge of the burden thereon into the furnace. The burden of coke,iron ore and limestone is charged into the big bell hopper from thesmall bell in the usual manner. Four conduits 10 are connected to thetop of the blast furnace 2 and the blast furnace gas passes upwardlytherethrough to a dust catcher 12. Each pair of conduits 10 merge into asingle conduit 14 so that there are two conduits 14 passing up alongsidethe dust catcher 12. A bleeder valve 16 is arranged at the top of eachconduit 14. From the top of the conduits 14 the gas passes throughbranch passages 18 to the top of the dust catcher 12. The gas thenpasses downwardly through conical passage 20 of the dust catcher andupwardly States Patent C F Patented Sept; 29, 1959 through passage 22 totakeoff 24. When the direction of gas travel is reversed at the bottomof passage 20 flue dust is separated out and falls into a plurality ofconical hoppers 26 at the bottom of the dust catcher. Four such hoppersare shown and a conduit 28 is attached to the bottom of each hopper.Each conduit 28 has two branches 30 which lead to a secondary hopper 32at the top of the blast furnace 2. Hopper 32 surrounds the hopper 4 andthe bottom thereof is closed by big hell 6. The conduit branches 30 arearranged so that they pass into the hopper 32 approximately forty-fivedegrees apart.

The operation of my device is as follows:

The blast furnace gas passes continuously from the top of the blastfurnace 2 to the dust catcher 12 where the flue dust is continuouslyseparated out into the hoppers 26. From here the dust passes throughconduits 28 and 30 to the secondary hopper 32. When the burden has beencharged to the top of the big bell hopper the big hell 6 is lowered andthe burden along with the flue dust in the hopper 32 passes downwardlyinto the furnace 2. The big bell 6 is then raised to close the hoppers 4and 32 and the charge of coke, iron ore and limestone is charged ontothe big hell 6 from the small bell (not shown) in the usual manner. Theoperation is then repeated.

While one embodiment of my invention has been shown and described itwill be apparent that other adaptations and modifications may be madewithout departing from the scope of the following claims.

I claim:

1. In a blast furnace the combination comprising a dust catcher, a bigbell, a main big bell hopper for receiving the furnace burden, asecondary big bell hopper on the 7 outside of said main big bell hopper,said hoppers being open at the bottom and adapted to be closed by saidbig bell, means for delivering blast furnace gas from said furnace tosaid dust catcher, and means for delivering flue dust from said dustcatcher to said secondary big bell hopper.

2. In a blast furnace the combination comprising a dust catcher, a bigbell, a main big bell hopper for receiving the furnace burden, asecondary big bell hopper on the outside of said main big bell hopper,said hoppers being open at the bottom and adapted to be closed by saidbig bell, a conduit leading from said blast furnace to the top of saiddust catcher for carrying blast furnace gas thereto, and a plurality ofconduits leading from the bottom of said dust catcher to said secondarybig bell hopper for carrying flue dust thereto at spaced points aroundits periphery.

References Cited in the file of this patent UNITED STATES PATENTS

